# What Are Cores

> An introduction to Cores

- Web page: https://documentation.federated.computer/self-hosted/cores/what-are-cores/

A **Core** is a bundle of open source business software — pre-configured to work together — running on **CoreServer**, Federated's custom operating system. CoreServer is installed on a virtual machine you own and provision at your cloud provider. Federated manages the software layer; you own the underlying infrastructure.

Each Core is registered to your account with its VM's IP address. Each Core is one installation, billed per month at your tier's rate: $0 on Free, $35 on Developer, or $10 on Platform. There is no membership fee.

## Core States

A Core moves through several states during its lifecycle:

- **Available** — The Core has been allocated to your account but provisioning hasn't started yet.
- **Provisioning** — The Provisioner is actively setting up the Core. This typically takes a few minutes.
- **Active** — The Core is live and operational, accessible at its assigned IP address.
- **Failed** — Provisioning encountered an error. Contact support if a Core is stuck in this state.
- **Decommissioned** — The Core has been removed from your account. Your underlying VM remains yours, but CoreServer will no longer function on it.

## Core Add-ons

Each Core can have optional add-ons attached to it: Backups, Monitoring, and Customer Service. Add-ons are billed per Core, per month, at the same price on every tier. Technical support isn't an add-on; it comes with your tier. See [Add-ons](https://documentation.federated.computer/self-hosted/plans-and-pricing/#add-ons) for pricing and details.

## Core Limits

No tier sets a hard limit on the number of Cores. The Platform tier is intended for accounts running more than 100 installations within 3 months. Contact support if you need to confirm your Core limit.